locking, percpu counters: introduce separate lock classes
Impact: fix lockdep false positives
Classify percpu_counter instances similar to regular lock objects --
that is, per instantiation site.
The networking code has increased its use of percpu_counters, which
leads to false positives if they are treated as a single class.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/percpu_counter.h b/include/linux/percpu_counter.h
index 9007ccd..96bdde3 100644
--- a/include/linux/percpu_counter.h
+++ b/include/linux/percpu_counter.h
@@ -30,8 +30,16 @@
#define FBC_BATCH (NR_CPUS*4)
#endif
-int percpu_counter_init(struct percpu_counter *fbc, s64 amount);
-int percpu_counter_init_irq(struct percpu_counter *fbc, s64 amount);
+int __percpu_counter_init(struct percpu_counter *fbc, s64 amount,
+ struct lock_class_key *key);
+
+#define percpu_counter_init(fbc, value) \
+ ({ \
+ static struct lock_class_key __key; \
+ \
+ __percpu_counter_init(fbc, value, &__key); \
+ })
+
void percpu_counter_destroy(struct percpu_counter *fbc);
void percpu_counter_set(struct percpu_counter *fbc, s64 amount);
void __percpu_counter_add(struct percpu_counter *fbc, s64 amount, s32 batch);
@@ -85,8 +93,6 @@
return 0;
}
-#define percpu_counter_init_irq percpu_counter_init
-
static inline void percpu_counter_destroy(struct percpu_counter *fbc)
{
}